Thimerosal is an organic mercury compound of the formula: ##STR1## This compound is used as a bacteriostatic agent or preservative in certain biological vaccines, as well as intermediates, buffers, diluents and cleaning and disinfecting reagents used in the manufacture of vaccines, and also as an inactivating agent for certain whole cell vaccine materials, and, as a result, is present in small quantities in effluent streams from vaccine manufacture. The primary contributors to the thimerosal concentration in the effluent are discarded whole cell supernatant and unused buffers. Although such effluent streams contain only small quantities of such organic mercury compound, in the 100's ppm range, such quantity is unacceptably high for disposal by simple sewering or other discharge to water bodies. Environmental regulation requires that the quantity of mercury discharged be less than 3 ppb.
Dilution of the effluent stream is not a practical alternative in view of the roughly 10,000 fold decrease in quantity of organic mercury required. Prior to the present invention, the applicant was unaware of any proposal which would decrease organic mercury levels in vaccine manufacture effluent streams to environmentally-acceptable acceptable levels, and which could accomplish the same in an efficient and inexpensive manner.